EC2: Fix additional files on small+builder AMIs

The file /usr/local/etc/ssl/cert.pem is not present on "small" and
"builder" AMIs, so we don't need to add it to METALOG.

Fixes:	2b0ffc0ee4 ("EC2: metalog_add missing files from packages")
MFC after:	3 days
Sponsored by:	https://www.patreon.com/cperciva

release/tools/ec2-builder.conf

@@ -68,7 +68,6 @@ vm_extra_pre_umount() {
 
 	# Add files from packages which weren't recorded in metalog
 	metalog_add_data ./usr/local/etc/dhclient.conf
-	metalog_add_data ./usr/local/etc/ssl/cert.pem
 
 	return 0
 }

release/tools/ec2-small.conf

@@ -51,7 +51,6 @@ vm_extra_pre_umount() {
 
 	# Add files from packages which weren't recorded in metalog
 	metalog_add_data ./usr/local/etc/dhclient.conf
-	metalog_add_data ./usr/local/etc/ssl/cert.pem
 
 	return 0
 }